Re: [PATCH v4 02/13] dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:

Pre-existing issues:
- [High] Missing subnode updates for the Milos Iris VPU enforce a DoS-vulnerable SMMU configuration.
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commit 63b882fd7198eab0ac9d5c0a3932a253f2082c86
Author: Vikash Garodia <vikash.garodia@oss.qualcomm.com>

dt-bindings: media: qcom,sm8550-iris: Add context bank subnodes

This commit updates the sm8550-iris device tree binding to move SMMU stream
definitions into separate context bank subnodes. This addresses an issue where
placing all streams in a single top-level iommus property failed to prevent
non-pixel buffers from landing in the restricted low 600MB of IOVA space,
which caused unhandled SMMU page faults and system reboots.

> diff --git a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> index 0400ca1bff05d..6ee9d23554cff 100644
> --- a/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> +++ b/Documentation/devicetree/bindings/media/qcom,sm8550-iris.yaml
> @@ -98,10 +98,10 @@ required:
>    - interconnect-names
>    - resets
>    - reset-names
> -  - iommus

[Severity: High]
This is a pre-existing issue, but does the qcom,milos-iris.yaml binding
also need to be updated to support this fix?

Currently, qcom,milos-iris.yaml still mandates a top-level iommus property
under the required block:

Documentation/devicetree/bindings/media/qcom,milos-iris.yaml:
required:
  - compatible
...
  - iommus

Device trees for Milos cannot adopt the subnode fix without failing schema
validation. This forces the DoS-vulnerable monolithic SMMU configuration
where unprivileged userspace or remote video playback can trigger VPU
processing and DMA allocations below 600MB, resulting in SMMU page faults
and spontaneous reboots.

The SM8750 VPU update was successfully resolved in follow-up commit
"dt-bindings: media: qcom,sm8750-iris: Add context bank subnodes", but
Milos appears to remain unaddressed.

Should qcom,milos-iris.yaml be updated to remove the top-level iommus
requirement similarly to this file?

>    - dma-coherent
>  
>  allOf:

[ ... ]

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Sashiko AI review · https://sashiko.dev/#/patchset/20260914-vpu_iommu_iova_handling-v4-0-9b9074a73c41@oss.qualcomm.com?part=2